// Numbas version: finer_feedback_settings {"name": "LM05 Determinant of a 2x2 matrix", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "LM05 Determinant of a 2x2 matrix", "tags": [], "metadata": {"description": "", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "

The determinant of a 2x2 matrix:

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Calculate the determinant of the following 2X2 matrices.

", "advice": "

Determinant

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The detrminant of a 2x2 matrix can be calculated using the following process:

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$$
\\begin{vmatrix}
a & b \\\\
c & d \\\\
\\end{vmatrix} = ad-bc.
$$

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Example

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For $A = \\var{nonzerodet2},$

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we have that,

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$$
\\begin{vmatrix}
\\var{nonzerodet2[0][0]} & \\var{nonzerodet2[0][1]}\\\\
\\var{nonzerodet2[1][0]} & \\var{nonzerodet2[1][1]}\\\\
\\end{vmatrix}=(\\var{nonzerodet2[0][0]})(\\var{nonzerodet2[1][1]}) - (\\var{nonzerodet2[0][1]})(\\var{nonzerodet2[1][0]}) =\\var{detnonzerodet2} 
$$ 

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Use this link to find some resources which will help you revise this topic.

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$$
A=\\var{nonzerodet2}
$$

\n

\n

$
\\text{What is the value of}\\begin{vmatrix}
A
\\end{vmatrix}?
$

\n

answer:[[0]]

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$$
m=\\var{zerodet1}
$$

\n

\n

$
\\text{What is the value of}\\begin{vmatrix}
M
\\end{vmatrix}?
$

answer:[[0]]

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